Four-Wave-Mixing-Based Phase-Sensitive Amplification of Pulsed Signal in Fibers

The four-wave-mixing-based phase-sensitive amplification of pulsed signals is analytically investigated, taking into account the pump depletion and the self- and cross-phase modulation (SPM and XPM) effects of the pumps and signals. Formulas for output phase and power are derived. It is found that, for a single-pulse signal input, the SPM/XPM of the signal will cause frequency chirping to the output; for a pulse-sequence, the amplitude-fluctuation of the input signal will destroy the phase regeneration through the SPM/XPM. In addition, the amplified signal pulse will initially be compressed and distorted, and then it will get broadened due to pump-depletion.